Wafer cassette used in high temperature baking process

ABSTRACT

A wafer cassette for consolidation in process of high temperature baking is provided. The wafer cassette includes one front end member, two sidewall plates, one back end member, a plurality of fixture slots, two resilient sheets and two supporting rods. By using this wafer cassette in high temperature baking process, the chance of having the wafer damage is minimized.

FIELD OF THE INVENTION

The present invention relates to a wafer cassette. More particularly, the present invention relates to a wafer cassette used in high temperature baking process.

DESCRIPTION OF THE PRIOR ART

In the semiconductor fabrication industry, the wafer processing into IC (integrated circuit) chips often includes several steps where the wafers are repeatedly processed, test, stored and transported. Due to the delicate nature of the wafers and their extreme value, it is vital that they are properly protected throughout this procedure. One of the purposes of the wafer cassette is to provide this protection.

In high temperature baking process, a wafer cassette, which is made by metal and can stand heat up to three hundred centigrade degrees, is used. However, during the baking process, the wafer is easy to have some damages in the edge of the wafer or the wafer can be broken when the wafer cassette is in process.

Referring to FIG. 1, it is a perspective view drawing of the wafer cassette according to one embodiment of the prior art. A wafer cassette 100 is used to transport and store the wafers. The wafer cassette 100 includes one front end member 110, two sidewall plates 120, one back end member 130, a plurality of fixture slots 140, two cylindrical sticks 150 and two supporting rods 160. The sidewall plates 120 are respectively fixed between the front end member 110 and the back end member 130. A plurality of fixture slots 140 are disposed in each of the sidewall plates 120. The two cylindrical sticks 150 are respectively disposed at the bottom of each sidewall plates. And the supporting rods 160 are fixed between the sidewall plates 120 and the cylindrical sticks 150.

The front end member 110 and the back end member 130 are used to protect the wafer. A plurality of fixture slots 140 are used to hold the wafers. The cylindrical stick 150 is used to support the wafer and is made by glass. And because the contact area of the cylindrical stick 150 with the wafer is small, it is difficult to enhance the cushion when the cylindrical stick 150 contacts with the wafer and the wafer is easy to have some damages in the edge of the wafer or the wafer will be broken.

SUMMARY OF THE INVENTION

According to the description of the prior art, the wafer cassette used in high temperature baking process where the wafer is easy to be collided with the cylindrical stick. Therefore, a resilient sheet is provided to reduce the degree of the collision. The probability to have some damages in the wafer is reduced.

One aspect of the present invention is to provide a wafer cassette with a structure that prevents the wafer from colliding. Another aspect of the present invention is that the material of the substrate must be able to stand heat at less three hundred centigrade degrees, because the wafer cassette is used in high temperature baking process.

In one embodiment, a wafer cassette is used in high temperature baking process. The wafer cassette includes one front end member, two sidewall plates, one back end member, a plurality of fixture slots, two resilient sheets and two supporting rods.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompany drawings incorporated in and forming a part of the specification illustrate several aspects of the present invention, and together with the description serve to explain the principles of the invention. In the drawings:

FIG. 1 is a perspective view of a wafer cassette according to one embodiment in the prior art.

FIG. 2 is a perspective view of a wafer cassette according to one preferred embodiment of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT

The following is the detailed description of the present invention, which describes the wafer cassette used in high temperature baking process, but the detailed structure composition and the operating theory are not discussed. The portions relating to the conventional techniques are briefly described, and the parts of the drawings are not proportionally drafted. While embodiments are discussed, it is not intended to limit the scope of the present invention. Except expressly restricting the amount of the components, it is appreciated that the quantity of the disclosed components may be greater than that disclosed.

When the wafer had been tested, it is necessary to put the wafer in the furnace to dry the inks, which are the marks for error chips. However, the wafer would have some damages in the edge of the wafer or the wafer would be broken during the high temperature baking process. The present invention is to provide an improved structure of the wafer cassette in high temperature baking process.

Referring to FIG. 2, it is a perspective view of the wafer cassette according to one preferred embodiment of the present invention. A wafer cassette 200 is used to transport and store the wafers. The wafer cassette 200 includes one front end member 210, two sidewall plates 220, one back end member 230, a plurality of fixture slots 240, two resilient sheets 250 and two supporting rods 260. The sidewall plates 220 are respectively fixed between two ends of the front end member 210 and two ends of the back end member 230. A plurality of fixture slots 240 are disposed in each of the sidewall plates 220. The resilient sheets 250 are respectively disposed at the bottom of each sidewall plates. And the supporting rods 260 are fixed between the sidewall plates 220 and the resilient sheets 250..

Still referring to FIG. 2, the resilient sheets 250 of the present invention are used to protect the wafer. The material of resilient sheets is metal and can stand heat up to three hundred centigrade degrees. In addition, the metal of the resilient sheet cannot be electroplated because it would pollute the wafer. On the other hand, the sheets can be the material can stand heat up to three hundred centigrade degrees without melting. The resilient sheets have a ramp to increase the contact area with the wafer and enhance the cushion when the resilient sheet is contacted with the wafer.

The resilient sheets 250 could be various shapes with springiness to avoid hitting against the wafers in high temperature baking process. The areas of the edge of the wafers are directly contacted with the resilient sheets. As long as more areas directly contacted with the resilient sheets, the opportunity of the wafers' damages is reduced.

The foregoing description is not intended to be exhaustive or to limit the invention to the precise forms disclosed. Obvious modifications or variations are possible in light of the above teachings. In this regard, the embodiment or embodiments discussed were chosen and described to provide the best illustration of the principles of the invention and its practical application to thereby enable one of ordinary skill in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. All such modifications and variations are within the scope of the invention as determined by the appended claims when interpreted in accordance with the breadth to which they are fairly and legally entitled. 

1. A wafer cassette used in high temperature baking process, comprising: a front end member; two sidewall plates oppositely disposed at two ends of said front end member; a back end member disposed between said two sidewall plates; and two resilient sheets with curved portion oppositely disposed at the bottom of said two sidewall plates.
 2. The wafer cassette of claim 1, wherein each of said sidewall plates has a plurality of vertical slots and an horizontal supporting rod.
 3. The wafer cassette of claim 1, wherein said resilient sheet is disposed at the bottom of said sidewall plate.
 4. The wafer cassette of claim 1, wherein said resilient sheet is connected to said supporting rod.
 5. The wafer cassette of claim 1, wherein said sidewall plate includes a plurality of fixture slots.
 6. The wafer cassette of claim 5, wherein said fixture slot is used to dispose the wafer.
 7. The wafer cassette of claim 1, wherein said resilient sheets is made of metal.
 8. The wafer cassette of claim 7, wherein said resilient sheets can stand heat up to three hundred centigrade degrees.
 9. The wafer cassette of claim 1, wherein said resilient sheets has a ramp to increase the contact area in the wafer. 